This invention relates generally to milking machines and more particularly to a teat receiving milking liner or inflation for use with a milking machine of the vacuum pulsator type.
Prior art milking liners commonly used have been made from various rubber and rubber-like compounds formed in the shape of a tube which has a uniform inner diameter. In order to form a mouthpiece for receiving an animal teat a rigid ring member is inserted in one end of the liner and is of a much larger diameter than the diameter of the liner. The expansion of the liner at the teat receiving end with the ring in place causes rubber fatigue and deterioration so that the teat receiving end prematurely distorts in shape so that it will no longer properly stay on the teat or in many cases breaks down completely.
The milking liner of the present invention provides a teat receiving end portion which is tapered to a smaller diameter than the diameter of the main body portion of the tubular liner. A further embodiment of the invention provides a milking liner having a teat receiving end portion which is tapered to a reduced diameter and further has a steadily decreasing wall thickness throughout the length of the taper.
As a result of the novel design of the teat receiving end portion of the liner of the present invention there is a better fit with the animal teat than was possible with prior art liners.
Moreover, because the rubber in the reduced diameter portion seeks to return to its original reduced shape and size after the ring is removed, even with rubber fatigue caused by continuous usage, the liner still maintains an adequate fit on the animal teat.
A further object and advantage of the present invention resides in the fact that the reduced diameter and reduced wall thickness at the teat receiving end of the liner helps minimize the chances of the teat channel being choked off or of other causes of teat irritation and inflammation which can lead to the infectious condition known as mastitis.
Other and further objects and advantages of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments of the present invention and the principles thereof and what are now considered to be the best modes contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.